纳米Cr3C2颗粒在Co-Ni复合镀液中的分散稳定性研究

采用超声破碎法制备了含纳米Cr3C2颗粒的钴镍镀液,研究了未加分散剂,以非离子型高分子分散剂改性和以阴离子分散剂改性三种情况下的镀液性能。通过激光粒度仪、镀层中颗粒复合量等测试方法对纳米Cr3C2颗粒钴镍镀液的稳定性进行了表征。结果表明,含纳米Cr3C2颗粒钴镍镀液通过阿拉伯树胶高分子型分散剂改性后,镀液的稳定性最佳,当阿拉伯树胶添加量为0.3 g/L,超声时间为0.5 h时,所得纳米Cr3C2颗粒钴镍镀液的稳定性最好。     

正交实验优化纳米ATO浆料分散工艺

运用正交实验法研究了超声时间、pH值、分散剂种类、分散剂用量以及高速搅拌时间对纳米ATO浆料的分散稳定性的影响。结果表明,当分散剂为硅烷偶联剂KH-570、分散剂用量20%,超声分散时间2 h,pH值为10,高速分散时间为2h的条件下,纳米ATO水性浆料分散比较均匀。利用激光粒度分析仪测定分散均匀后的纳米ATO浆料,发现绝大部分的纳米ATO粒径都在150 nm以内,说明该工艺可以适用于纳米ATO浆料的分散。     

水性纳米掺锑二氧化锡(ATO)浆料的研制

采用硅烷偶联剂对纳米掺锑二氧化锡(ATO)粒子表面进行化学改性,以分散剂对其进行物理包覆,调节分散工艺、体系黏度和pH,获得了稳定性可达到两个月以上的水性纳米ATO浆料.傅立叶红外光谱分析表明,硅烷偶联剂可以有效地包裹在纳米粒子表面.当采用硅烷偶联剂KH570,其用量为纳米ATO粒子质量的1.5%时,包覆效果最好;选用嵌段型分散剂3275,其用量为体系质量的0.2%时,分散效果最好;当体系黏度大于88 mPa·s和pH=10时,浆料稳定性最好.透射电子显微镜观测表明,纳米ATO粒子获得了良好分散.     

超支化分散剂与表面活性剂复配对颜料分散体系的影响

超支化聚合物的合成与应用是目前研究的热点.应用自制的超支化分散剂(Hyperb舢ched dispersant,HPD)与不同的表面活性剂复配,制备水性颜料分散体系,研究其他表面活性剂种类、超支化分散剂与表面活性剂比例等条件对颜料分散体系的粒径及其分布、离心、稳定性等性能的影响.实验结果表明:超支化分散剂与非离子表面活性剂复配比为7:3、与阴离子表面活性剂复配比为6:4时,体系的分散性和稳定性较好.超支化分散剂与阴离子分散剂复配效果较好.     

纳米ATO导电浆料的分散稳定性

将纳米ATO粉体分散于溶剂中制备成纳米ATO导电涂料.通过黏度测定和沉降实验,讨论了分散剂种类、pH等参数对制备浆料的影响,进行优化筛选.经粒径分布测定及扫描电镜观察,最终制得分散稳定性较好的纳米ATO浆料.     

纳米ATO隔热涂料中水性分散浆料的制备和研究

纳米氧化锡锑(ATO)是制备透明隔热涂料的理想材料,本研究以摩尔质量比为Sb∶Sn=7∶93的ATO粉体和一定比例的分散剂,制备得到了分散性能良好的ATO水性分散浆料,浆料的可见光透过率高达80%,且浆料中粒子的平均大小为0.35μm。用XRD、FT-IR、激光粒度仪等对浆料的性能进行表征,并对浆料的稳定性和透光性进行研究,实验所制备的ATO浆料具有优良的稳定性和透光性,且制备的ATO隔热涂料具有良好的隔热性能。     

ATO/APU纳米复合透明隔热涂料的制备与性能研究

以纳米氧化锡锑(ATO)水性浆料为隔热材料,水性聚氨酯树脂(APU)为成膜物质制备出ATO/APU纳米复合透明隔热涂料。对悬浮ATO粒子的分散稳定性、ATO/APU复合涂膜的物理性能、可见光-近红外透射光谱透过率、隔热性能进行研究。结果表明,纳米ATO粉体通过偶联剂KH-550改性后,与APU复合制得了分散稳定的纳米复合涂料;ATO/APU复合涂料不仅具有良好的成膜性能,而且在保持可见光透过率83.0%时,红外阻隔率达到70%,隔热后温差能保持在6℃左右,复合涂料具有良好的隔热性能。     

纳米ATO浆料分散性能的影响因素研究

采用硅烷偶联剂对纳米掺锑二氧化锡(ATO)粒子表面进行化学改性,将纳米ATO粉体分散于蒸馏水中制备成纳米ATO浆料,研究了分散剂种类,分散剂用量,硅烷偶联剂,硅烷偶联剂用量,分散时间和pH等参数对ATO纳米浆料分散效果的影响。当采用硅烷偶联剂KH560,其用量为浆料总质量的0.8%;嵌段型分散剂3275,其用量为浆料总质量的0.6%;pH=10时,可制备分散性能良好的纳米ATO浆料。     

基于正交实验的纳米ATO浆料的分散稳定性研究

采用正交实验对纳米掺锑氧化锡(ATO)浆料的制备条件进行了优化,研究了磁力搅拌时间、分散剂种类、分散剂用量、pH值和超声分散时间对纳米ATO浆料分散稳定性的影响。实验结果表明:在磁力搅拌时间为1 h,分散剂用量为10%,pH值为10,分散剂为4#和超声分散时间为30 min的条件下,纳米ATO浆料的分散稳定性最好。     

抗静电腈纶用纳米金属氧化物的分散工艺研究

选择氧化锌(Zn O)、铝掺杂氧化锌(AZO)、氧化锡锑(ATO)以及ATO包覆硫酸钡(Ba SO4)4种纳米粉体抗静电剂球磨分散得到其水相悬浮液,利用喷雾共混的方法制备改性聚丙烯腈(PAN)纺丝原液,进行湿法纺丝,研究了表面活性剂种类、研磨工艺对纳米粉体在水相中沉降性的影响,以及改性PAN纤维的抗静电性能。结果表明:采用自制的非离子/阴离子表面活性剂复配物(FCY)作为分散剂,FCY质量分数(相对于纳米粉体)为2%,研磨时间3 h,纳米粉体的水相分散效果好,分散工艺对4种纳米粉体均有很好的适用性;ATO改性PAN纤维具有较好的抗静电效果,当添加ATO质量分数为2.0%时,PAN纤维的体积比电阻为3.1×109Ω·cm,具有耐久性,可以满足抗静电织物对原料的要求。     

纳米二氧化钛的表面改性研究

采用不同的表面活性剂三乙醇胺、十二烷基硫酸钠(SDS)、聚乙烯吡咯烷酮(PVP)对纳米二氧化钛进行表面改性处理。对不同表面活性剂处理的纳米二氧化钛采用沉降法来表征纳米粉体在水中的分散性,目的是日后用来制备更均匀的复合薄膜。研究结果表明:三乙醇胺与其他两种表面活性剂混合使用较单种表面活性剂处理后的纳米二氧化钛其分散效果会更好。分散纳米二氧化钛效果最佳的表面活性剂为三乙醇胺与十二烷基硫酸钠的混合物(质量比为2∶1),表面活性剂总用量为30%(质量分数),采用搅拌和超声时间都为15 min,纳米二氧化钛的初始沉降时间为2.5 h,完全沉降时间大于120 h。     

表面活性剂分散碳纳米管的进展

碳纳米管容易聚集成束或缠绕,严重制约了碳纳米管的应用。通过表面功能化可增强碳纳米管在溶剂中的溶解性和其他基质材料中的分散性,从而提高碳纳米管的实际使用价值。用表面活性剂分散碳纳米管的方法进行综述,总结了各种表面活性剂的优缺点并提出了表面活性剂在碳纳米管应用的展望。     

Synergistic effect of polymer-surfactant mixtures on the stability of aqueous silica suspensions

The aim of the present work was to investigate the effect of cationic/nonionic surfactant mixtures on the dispersion and flocculation behavior of aqueous silica suspensions. In the study dodecylamine (DDA) was used as the cationic surfactant and polyethylene oxide-polypropylene oxide-polyethylene oxide (PEO–PPO–PEO) triblock copolymers were employed as the nonionic surfactant. The dispersion and flocculation behavior of aqueous silica suspensions were studied mainly by turbidity measurements at low solids loading (0.05 vol.%) to observe the stability of the system for a given time period. Rheological measurements were performed at higher solids loadings to determine the viscosity as a function of shear rate. Adsorption behavior of single and mixed surfactants onto silica surface was studied using a total organic carbon analyzer.Results of the study showed that dispersion and flocculation behavior of aqueous silica suspensions depends on the type and concentration of surfactant, cationic/nonionic surfactant ratio and surfactant addition sequence to the system.     

Associative polymer/latex dispersion phase diagrams II: HASE thickeners

The colloidal interactions of HASE associative polymers and latexes in the presence of surfactant are complicated and subject to a number of variables. Both bridging and depletion flocculation can occur, in addition to good particle dispersion. Dispersion phase diagrams have been developed to help visualize these interactions. The various dispersion states can have a significant effect on coating formulations and film properties. Examples of dispersion phase diagrams are presented for a model HASE anionic associative thickener and various model latexes in the presence of sodium dodecyl-sulfate and nonionic surfactants. The major variables affecting dispersion behavior are associative polymer concentration, latex particle size, latex surface hydrophobicity, electrolyte concentration, and surfactant concentration. The dispersion phase behavior of the HASE systems is compared to that of HEUR thickened systems reported previously. A significant difference is that much less bridging flocculation is observed in the HASE systems. In addition, nonionic surfactants induced depletion flocculation in the HASE systems but not in the HEUR systems.     

Novel preparation method for improving the dispersion of ionic liquid‐modified montmorillonite in poly(ethylene terephthalate)

Thermally stable ionic liquids (ILs) were used to modify clay nanoparticles for use in the preparation of poly(ethylene terephthalate)/clay nanocomposites. Nanoclays with smaller particle size distributions were prepared with a two‐step centrifugation method that removed large particles from commercial montmorillonite (MMT). Scanning electron microscopy of aqueous dispersions of MMT and centrifuged clay (CMMT) illustrated that the average particle size of CMMT in water was much lower than that of MMT in water. Both CMMT and MMT were modified with imidazolium‐ and phosphonium‐based ILs. Fourier transform infrared spectroscopy revealed that the surfactants were associated with the clay surface. Thermal gravimetric analysis results indicated that clays modified with thermally stable ILs degraded above 300°C and could survive PET processing temperatures. Transmission electron microscopy for nanocomposites revealed an improvement in the dispersion of centrifuged nanoclays (modified with both imidazolium and phosphonium ILs) into the polymer matrix compared to non‐centrifuged modified MMT with larger particle sizes. X‐ray diffraction and differential scanning calorimetry data indicated that particle size distributions have a significant effect on the dispersion and rate of crystallization of nanoclays modified with imidazolium surfactants. There was, however, a less important effect of centrifugation on the dispersion of nanoclays modified with phosphonium surfactants. POLYM. COMPOS. 37:1259–1266, 2016. © 2014 Society of Plastics Engineers     

溶胶-凝胶法制备纳米锑掺杂氧化锡的团聚消除

采用溶胶-凝胶法制备纳米锑掺杂氧化锡(antimony doped tin oxide,ATO)前驱体,然后通过烘干、微波、真空以及超临界流体干燥(supercritical fluid drying,SCFD)等方式干燥醇凝胶,并在600℃下进行热处理,考察干燥方式对最终产物纳米ATO团聚情况的影响.利用XRD、SE...     

硅烷偶联剂KH570对纳米SiO2的表面改性及其分散稳定性

采用硅烷偶联剂KH570对纳米SiO₂实现表面改性,并利用透射电镜（TEM）、粒径分析、Zeta电位、红外光谱（FTIR）等方法对改性后纳米SiO₂的表面结构和在有机介质中的分散稳定性进行分析表征。结果表明,通过硅烷偶联剂KH570表面改性后,颗粒表面覆盖了硅烷偶联剂的有机官能团,提高了SiO₂纳米颗粒在水溶液中的Zeta电位,降低了颗粒团聚程度。改性后的纳米SiO₂粉体在有机溶剂中的团聚块体尺寸明显减小,从200 nm降低到不足100 nm。     

纳米锑掺杂氧化锡的表面改性

将纳米锑掺杂氧化锡(antimony doped tin oxide,ATO)分散于乙醇与水的混合改性介质中,利用硅烷偶联剂KH-570与纳米ATO表面羟基的脱水反应以及硅烷偶联剂间的缩合反应,制得了KH-570包覆的纳米ATO粉体。用FTIR、XPS、TG、TEM对纳米ATO粉体的表面结构进行了表征,并通过亲油性的测试,考察了其分散稳定性。结果表明,在ATO纳米粒子表面接枝上了7.36%～7.73%(质量分数)的KH-570,改性后的纳米ATO粒子的亲油性及分散性得到大幅度提高,改性ATO在正丁醇中能够稳定分散100 h以上。     

非离子表面活性剂作用下分散染料对棉沾色机理研究

通过研究非离子表面活性剂结构和浓度对C.I.分散红60增溶量、分散体系的高温稳定性、C.I.分散红60的上染率以及染浴中染料残留量的影响,探讨了在非离子表面活性剂作用下C.I.分散红60对棉沾色的机理。结果表明:非离子表面活性剂用量较低(0.5 g/L左右)时,分散体系有较好的高温稳定性,此时非离子表面活性剂对分散染料的增溶量为影响沾色的主要因素,分散染料的增溶有利于减少其对棉的沾色;随着非离子表面活性剂用量的增加(≥1 g/L),染料的上染百分率和分散体系的高温稳定性降低,分散染料对棉的沾色加重,沾色等级降低到2级。     

Some Surface Properties of Polysorbates and Cetyl Trimethyl Ammonium Bromine Mixed Systems

Mixed surfactant solutions consisting of cationic/nonionic surfactants were prepared in different compositions of the components in aqueous solution in order to determine the surface properties. The critical micelle concentration (CMC) of aqueous solutions of the individual surfactants cetyl trimethyl ammonium bromide (CTAB) and polysorbate nonionics, and their mixtures are determined at different proportions. The results show that there is synergistic behavior in mixtures at higher mole fraction of nonionic surfactant. The effect of the alkyl chain on the CMC is also determined.